John Mayer Digs Katy Perry's 'Roar'

John Mayer recognizes successful pop music when he hears it, and he figures that girlfriend Katy Perry's new song "Roar" will be a massive hit, for example, reports Billboard.

"In a way you get swallowed up by it, it's so big," he said. "Because it's such an incredibly big song that it doesn't need you to tell anybody, while you're eating lunch, [that] millions of people are going to be dancing on tables to that."